Best method to fix small crack?

[HighUintas]

While I was inletting my lock plate tonight , I realized that I cracked the oblique flat under the lock bolster. My clamp that is holding the barrel in came loose a time or two while inletting the bolster and the barrel worked its way up, removing some of the support there.

What's the best way to fix/stabilize a crack of this size in this location? I'm not sure how I'd work wood glue into that crack

[Stonehouse john]

FWIW, you can get wood glue to fully fill almost any size through-crack like that if you lay a bead of glue covering one side (the largest, longest side) of the crack and draw it into the crack by using a vacuum cleaner from the other side.  I use one of the thinner-bodied wood glues when I do this, like Tightbond III so it flows well.  Wood glue gives you the luxury of a little time to get it clamped just right. 
That said, I think CA (Super) glue would do a fine job on that crack as well.
Either way, test-clamp to close that crack before applying the glue and be ready to quickly re-apply the clamp as soon as you've run the glue into the crack.  I'd use clamp pressure on the corner of this one (with a tiny corner block) as pressure on only one side might shift the broken piece sideways.
That one looks like it should glue up nicely.

John

[bluenoser]

I like Stonehouse John's suggestion.  That approach has never occurred to me.  I have rubbed PVA glue (yellow carpenter's glue) into the crack on the top side and blown it through with compressed air, repeating as necessary.  It works but is very messy on the back side.  My go-to method any time there is any ability to flex the crack just a smidge is to rub glue into the crack and then flex the joint.  Repeat as necessary until glue appears all along the back side of the crack.  That method has worked very well for me.  It appears this crack should be easily flexed.

[Daniel Coats]

Is there any advantage to warming either the wood or glue or both to lower the viscosity.Warm not hot I'm guessing.

[Eric Krewson]

I would soak the crack with superglue and hold it closed with my thumb until it sets which will be just a few minutes.

Case in point on a Kibler SMR; I bought a Kibler kit that the previous owner said he didn't have time to put together, it was at a bargain price. When I got the kit I noticed the fore stock was cracked between the rear entry pipe and the lock. Having built a few rifles I could tell the initial owner had tried to pull the very tight barrel out of the stock by holding the barrel in one hand and the stock in the other and trying to snatch the barrel out.

Being a bow maker for over 25 years I have filled lot of cracks.

In this case the wood fit back together perfectly when squeezed shut so I gave it the superglue treatment that I described above.

The crack was almost 3" long and is barely visible now, it starts above the barrel pin.

[HighUintas]

Thank you all for the great suggestions. That idea about using a vacuum cleaner to pull the glue through the crack is creative! The creativity of people who build or work on muzzleloaders has impressed me thus far.

One other question. I have about 0.015 left to go to have the plate inletted completely. Will any glue that is in that crack or on the surface of the wood on the lock side wreak havoc on my chisel? Would one glue be preferable over the other to make be easier on my chisel? I assume that I should fix the crack before continuing to inlet the plate rather than finishing the plate inlet and then fixing the crack?

[Daryl]

Like Eric, I would use super glue, however, I would use the cyanocrylate(crazy glue) from a hobby store. It is available in many different viscosities,
super thin, thin, med and thick.
I would use the super thin as it will  wick to the extreme of the crack and seal it all.  I did this with a crack on my .69 about 20years ago and it is still solid,
even though being in a 'recoil' area & was caused by recoil to start with.

[P.W.Berkuta]

This crack will be quickly fixed with thin super glue as Eric & Daryl have already said. That crack is so small and in a location that it just begs to be superglued. Apply the THIN superglue into the crack and hold it closed with something other than your finger

[Stonehouse john]

High Uintas,

To answer your second question, neither wood glue nor CA (cyanocrylate) will do any harm to your tool's cutting edges once they're cured.  You'll do best to glue first before final shaping so there's no risk of something shifting during glue-up and leaving a visible line.  Also, the inletting will be easier and more accurate on material that's not wiggling around...

John

[HighUintas]

Thank you all for the help!  I'll pick up some thin crazy glue this evening and get back to it.

*I'm disappointed I didn't get a visit from Mike Brooks here to tell me not to make cracks in the first place 

[Daryl]

I also would NOT use my finger. I tend to be messy with crazy glue and would end up glued to the "work"

[Jim Evans]

Thank you all for the help!  I'll pick up some thin crazy glue this evening and get back to it.

*I'm disappointed I didn't get a visit from Mike Brooks here to tell me not to make cracks in the first place 

Maybe he's so Cracked Up about this crack that he couldn't respond. 

[Eric Krewson]

Another thing I do is soak the wood around the crack with multiple applications of superglue until it won't suck up any more. In the case of the crack I pictured above I really soaked the inside of the barrel channel with glue, not the outside because the wood wouldn't take stain if I did. This turns the wood into concrete and makes further cracking unlikely.

I posted this about hardening wood with superglue once and caught a lot of flack from the "experts" about my method being ineffective. One guy even contacted a tech rep at a company that marketed superglue so he could prove me wrong. Surprise, surprise the tech rep said their glue did harden wood like I said it would.

All of my lock inlets get a bead of superglue soaked in the wood around the inside of the mortise, just in case. Zap-A-Gap makes a glue that is thinner than water and will really soak into wood deeply, I used this exclusively until I ran out, now I use the dollar store stuff.

I have fixed hundreds of cracks in osage bow wood, only a dozen or so in gun building.

[HighUintas]

Jim, he was probably too busy just shaking his head 

Eric, thank you for that information. I wasn't able to find any super thin glue at the store, but I did get loctite brand liquid super glue. I tested it on a piece of scrap wood prior to using and the wood did seem to wick up the glue well. So I held the crack open a bit and squeezed in a few drops from the barrel channel side. Sure enough, it wicked right over to the lock mortise! I did notice that it seemed like the surrounding wood soaked up some of the extra, so I may give it an extra light surrounding the crack.

Thanks all!

[Scota4570]

Another thumbs up for super glue.  Use the kind marketed to wood workers and model airplane hobbyists.  The syuper market stuff I not as sure.   The thin one will wick into the crack, but medium viscosity works the same and is a bit less messy.    Hold the joint open and  putt the glue in the joint,  I then hold it shut as necessary with an object.  While holding it I apply a spritz of accelerator.  That sets the surface level glue in a few seconds.   No holding is required after that. 

[Daryl]

I used thick CA to seal a 1/2" wide (exacto knife) wound on the inside of my wrist (airplane building slip). The puddle of CA on my wrist wasn't setting up quickly enough as the blood was welling up under the lump of CZ, so I hit it with a spritz of accelerator. Instantly, tears shot out of both eyes - incredible stinging, but, it did harden the glue which stopped the bleeding.
A few days later, the lump fell off and the cut was completely healed.
CA was invented to seal large wounds in Korea.
I suspect the airplane CZ I used wasn't CDC approved, however no adverse actions/reactions occurred.

[Daniel Coats]

I used it to seal a cut I got while caping an antelope in the field. The cut was near the wrist so I held the tube in my clenched teeth and squeezed it into the cut and pinched the wound closed with the other hand. Sounds gruesome but it worked perfectly!

[P.W.Berkuta]

The best "superglue" I found is made by Bob Smith. His stuff last long when kept in the refrigerator and holds better than the grocery/hardware store brands.

[flehto]

W/ small cracks as shown, I first apply stain . let dry and then use the runny super glue. The super glue dissolves the stain and the crack becomes invisible. If possible, surgical tubing is used to close the crack. ......Fred